select from grouped data

Hello,

I have written this function to process some multiline text data into a
table with both text & numeric columns:

CREATE OR REPLACE FUNCTION get_final_energy ()
RETURNS TABLE (
jid text,
"timestamp" text,
scf integer,
energy double precision
)
AS $$
WITH a AS (
SELECT
jid,
regexp_split_to_table(totenergy_out, '\n') AS teo
FROM
results
),
b AS (
SELECT
results.jid,
results. "timestamp",
cast(
CASE WHEN split_part(a.teo, ' ', 2) = '' THEN
'0'
ELSE
split_part(a.teo, ' ', 2)
END AS integer) AS scf,
cast(
CASE WHEN split_part(a.teo, ' ', 3) = '' THEN
'0.0'
ELSE
split_part(a.teo, ' ', 3)
END AS double precision) AS energy
FROM
results,
a
WHERE
results.jid = a.jid
GROUP BY
results.jid,
results. "timestamp",
a.teo
--HAVING
-- scf = max(scf)
ORDER BY
timestamp ASC,
scf DESC
)
SELECT
*
FROM
b;

$$
LANGUAGE sql;

The output looks like:

jid | timestamp | scf | energy
------------+-----------------+-----+----------------
1250_1 | 20210805-114634 | 18 | -1316.43700819
1250_1 | 20210805-114634 | 17 | -1316.43700825
1250_1 | 20210805-114634 | 16 | -1316.4370097
1250_1 | 20210805-114634 | 15 | -1316.43700991
1250_1 | 20210805-114634 | 14 | -1316.43699775
1250_1 | 20210805-114634 | 13 | -1316.43699117
1250_1 | 20210805-114634 | 12 | -1316.43750771
1250_1 | 20210805-114634 | 11 | -1316.43805358
1250_1 | 20210805-114634 | 10 | -1316.43857192
1250_1 | 20210805-114634 | 9 | -1316.43070942
1251_1 | 20210806-062539 | 18 | -1316.43700819
1251_1 | 20210806-062539 | 17 | -1316.43700826
....

What I want is to get (for each group) the energy corresponding to the
maximum value of scf.

I appreciate any help,
Thanks,
Roger